Disposable multi-ply product



United States Patent 3,070,095 DISPGSABLE MULTI-PLY PRODUCT David Torr, 8 E. 74th St., New York, N.Y. No Drawing. Filed June 24, 1954, Ser. No. 439,140 13 Claims. (Cl. 128284) This invention isthat of a multi-layer, toilet-waterfiush-awayable napkin such as a disposable diaper, a pad for protecting the bed against wetting, or a catamenial device as a sanitary napkin or a vaginal tampon, and the like.

Many attempts have been made to produce the socalled disposable diaper. Although several different types are commercially available, some disadvantages still retard their more extensive use in spite of the undesirable job of washing linen diapers or the cost and inconvenience of the diaper services. None of the socalled disposable diapers could be adequately or safely flushed away by toilet water stream. Others are insufiiciently absorptive, or too coarse or rough or harsh in texture and provoke irritations. Still others are too bulky and wrinkle and crease so much between the wearers legs as to cause much discomfort.

These various disadvantages are overcome by the product of the invention which is so composed as to be readily completely flushed away by the toilet water stream, is thin, soft, and adequately flexible to avoid discomfort in its use or irritation by abrasion.

While the products of the invention may be more genenally embodied in a disposable diaper, their particular combination lends itself to their being embodied also as sanitary napkins, vaginal tampons, or pads for protecting beds or cots or other surfaces against wetting by children who have not yet developed control of their elimination and voiding or by older people who during illness or otherwise have temporary or extended loss of such control. All of these various possible embodiments are intended by the expression multilayer, toilet-waterfiush-awayable napkin. Sometimes the expression multiply may be used in place of multi-layer.

The make-up of the multi-ply, disposable napkin material of the invention includes three requisite parts, each of a particular character. These required parts are: (a) the body-touching sheet or ply, so-called because its exposed surface contacts the wearers body, (b) the waterimpervious sheet, and (c) an intermediate layer of, e.g., discrete particles in from finely divided to flake form of a dry, water-absorbent substance that in moist or wet state is harmless to the surface of the body contacted by the product.

The body-touching ply is a thin, soft, absorbent cellulose-type sheet. It is advantageously made of a fine soft paper of a quality at least such as in a good grade of facial tissue. It is of such quality so that in the dry state it does not abrade or irritate the skin. It is beneficially relatively loosely textured, for example, as in a soft quality facial or toilet tissue, but yet of sufiicient wet strength to retain its continuity and not tear while in the wet state on the wearer. This is desirable because, for example, it is not uncommon that when a diaper-wearing child only Wets the diaper, the wet diaper is not replaced and the child continues to wear it and will wet it again one or more times.

So long as it has the required softness, the bodytouching ply need not be restricted to a felted sheet, which is the preferred form, it may be a loose weave, for example, a fine grade gauze treated for softness. It can be made of cellulose, cotton, paper cotton, or even synthetic cellulose-like fibre, all of which and others like them are embraced by the expression cellulose-type." In thickness it can range from about one one-thousandth to about two one-hundredths or even about three onehundredths of an inch.

The water-impervious ply likewise can be composed of a cellulose-type sheet such as used for the bodytouching ply. However, the water-impervious sheet need not have the relatively open texture. It can be of fuller texture to provide somewhat greater strength, for it is the strongest of the three requisite component parts of the product.

Water-imperviousness is imparted to this sheet by application to one or both sides of it of a water-repellant coating that is inert or harmless to the skin of the wearer. Such coating can be of any suitable natural or synthetic wax, such as parafiin wax, and applied in known manner; or natural or synthetic resin, either rolled on or applied dissolved in a volatile solvent; or of lacquer.

However, whatever coating material is used should be applied prefenably only in quantity sufiicient to impart the water-imperviousness and should be one that leaves the coated sheet sufliciently flexible to avoid abrading the skin of the user. While this sheet can be as thin as the body-touching sheet, it desirably can be thicker, even up to twice that of the other sheet.

The water-impervious coating is applied to prevent wetting, and particularly soiling, of any outer garment worn next to the napkin of the invention. Generally, it is sufficient to coat only one side of the water-impervious sheet. Ordinarily, the coated side of this sheet can be the exposed surface of it in the assembled finished napkin. However, in many cases, it is advantageous to have the uncoated side as the exposed surface in the assembled product. That then presents a softer surface to the skin of the wearer and allows greater latitude in the coating materials that can be used.

That surface 'of the water-impervious sheet and also of the body-touching sheet that is not an exposed surface in the assembled finished napkin is conveniently referred to as the unexposed side of the water-impervious sheet or of the body-touching sheet respectively.

The intermediate layer is the principal water-absorbent portion of the product. The water-absorption by the intermediate layer is done essentially by, preferably discrete particles of, a dry water-absorbent substance of other than cellulosic origin and which in. the moist or wet state is harmless to the surface of the body contacted by it and inert to any other constituent of the napkin contacted by it. It can be of organic source and of synthetic or natural origin. For the most part, the discrete particles are finely divided, most advantageously between about two hundred and four hundred mesh. It can be also of somewhat larger size so long as the particles, if any should penetrate the exposed surface of the body-touching layer do not scratch or abrade or irritate the body, especially when the napkin or diaper is wet.

In some cases where the water-absorbent substance is of such nature that it can be prepared in very thin film form, for example, of about one one-thousandth to about two or three one-hundredths thickness, as can be done with many of those of organic origin, the water-absorbent substance can be used in flake form. The flakes could then be prepared, for example, by breaking such a film of the organic material into flakes of suitable size, or otherwise.

The intermediate layer can be included as one of the requisite components of the multi-ply napkin, for example, as discrete particles, by being incorporated into either surface of a supporting cellulose-type sheet similar in character to the body-touching sheet and of its thickness or of a thickness intermediate that and the water-impervious sheet. Alternatively, the water-absorbent substance also can be incorporated into the unexposed surface of the body-touching layer, or the unexposed sur- --face of the water-impervious layer when the water-impervious coating is applied to its exposed surface.

So long as the water-absorbent substance is harmless .and inert to the cellulose-type sheets and to the body of the wearer, the water-absorbent, or moisture-absorbent substance can he anyone, "or a mixture, of a wide variety of dry solid substances of other than cellulose origin. Among-such water-absorbent substances are organic substances of 'polysaccharide character, for example, Waterabsorbent, water-miscibleor water-soluble natural or synthetic gums such as karaya, tragacanth, guar gum (the refined endosperm of guar seed separated from the seed germ and hull, a cold water-soluble polysacchan'de consistingprincipally-of a complex carbohydrate polymer of galactose and mannose, and correctly termed a galactOmannan); 'algin; proteins such as blood or egg albumin;

and sponge .(natural 'or synthetic).

All of the foregoing water-absorbent materials are used in the dry, finely-divided state, although those that can -beformedinto a thin film can be disaggregated into relati'velyflexible flakesand then be used in the flake form. .As indicated, othersuchsubstances can be used so long as they are inert to the cellulose-type sheets and harmless to the bodyot the-wearer, and do not decompose in the ,presenceaofrmoisture, and .do not increase in temperature above body temperature by heat of absorption ofwater.

Theexpression *merely:physicallyimpregnated in the -appende'd claims intends that the discrete particles in .from 'finelyidivided toxflake form of the drywater-ab- 'sorbent organic'substance are: held in the claimed articles in a formdifferent from an adhesive vbondingsuch as a'could occur "from :depositing the particles from an aqueousslurry whereby there can be imparted to any wateruabsorbent substance which :becomes sticky when wetted with water, 1311 adhesive :bonding character that then would cause the particles adhesively to stick tothe fibres 'iofthecellulose-type sheets of the articleas wellas to one another .tolform'an adhesively coherent coating bind- .inglthe adjacentsheets together.

The products of the invention can be prepared readily by continuous machine processes, thereby providing low cost. For-example, the body-touching sheet can be made avai1able rolled up on arol-lerand so also the water- "impervious sheet. These'rolls can be mounted spaced apartfrom-one another, one :above the other, and ar- 'range'dso'that both of the sheets can be'rolled off towarda-common meeting point. When the moisture or water-absorbent substance is to be incorporated on its own separate cellulose-type sheet, a roll of that sheet is -1nounted so that the sheet coming oif of it can be fed towardthe-cornmonmeeting place "of, and between, the body-touching sheet and water-impervioussheet feeding -otr" their'respective rolls. :After the sheet for the'moisture-absohbent substance leaves its roll, it passes under a -sifting feeder for finely divided materials and the selected water-absorbent'substance or mixture is distributed over i the topsur'face of the sheet as it passes horizontally under "the sifter,'-'at a rate'to'apply, for example, from about "/twoo'r threegramsto twentygrams. per square foot of surface or more where indicated. The sheet thus hearing the loosely adhering moisture-absorbent material passes between a pair of superimposed press rolls, preferably operated cold, whereby the finely divided waterabsorbent material is pressed into the interstices of its carrier sheet which then is fed on between the other two sheets. Thereafter all three sheets continue together through another set of superimposed rollers. The latter functions merely to press the sheets together.

When the moistureor water-absorbent substance is not to be carried on its ownseparate sheet but instead is to be incorporated in the unexposed surface of either of the two other sheets, the roll of that one of the two which is to carry the substance is the lower one of the two rolls. It feeds out the sheet with the unexposed surface on top. That sheet is then fed under the sifting feeder to receive the moisture-absorbent substance. Thereafter the two sheets continue to the set of rollers which presses them together.

For the preparation of disposable diapers, the width of the sheets used can be the same as the width of the diapers. These can be sold on rolls from which can be .cut off any desired length, or they can be cut into selected lengths, for example, separated by suitable perforations or scoring.

The edges of the two or three sheets pressed together can be sealed by any suitableinnocuous adhesive or heat- .sealable polymer, either of which can be applied in known manner.

Bed pads to protect a bed surface against wetting can be prepared in substantially the same way as are the disposable diapers.

Catamenial pads can be prepared in relatively the same way by cutting themfromsheets of suitable width, for example, a strip of any suitable width cut from. a wide sheet, or may be stamped out by. suitable dies from the sheets.

Tampons can be prepared, for example, by selecting sheets of suitable widths or cutting such widths from -wider' sheets, and rolling theresulting strips into suitable tampon form; or .by rolling any number of turns of the moisture-absorbent layer (whether impregnated on a supporting cellulose-like sheet or any other) about a tampon core; .to either of whichthere can be attached -in any convenient known manner the strings for their removal after use. Alternatively, the discrete particles .(finely divided orflake) ofthe moisture-absorbent can :be coated over'aiformed tampon or its surface impreg nated with such absorbent.

.The'multi-layer disposable napkin of the invention is not limited to its several herein described uses. The

combination can be applied to other uses wherein its watersabsorbent layer serves effectively.

Thus it can serve-t0 absorb any other moisture or aqueousexudation from any body opening, natural or otherwise, for:example, asa bandage over any form of open wound.

Any of the moisture-.01 water-absorbent substances -can'be admixed with a suitable proportion under,'say, ten

vpercent and even as little as one-half percent, of a suit- ;able.capillary-penetrating assistant that will be inert to the water-absorbent and the fibre during storage, and

harmlessto the body in use.

The invention is not concerned with any specific meth- 0d of preparing any of the multi-layer, toilet-flush-awayable napkins of the invention. On the other hand, it is concerned with essentially the particular combination of multi-layer napkins of the disposable type.

'While the invention has been describedin relation to :certain specific embodiment of it, it is understood that various modifications and substitutions can be made in it within the scope of-the appended claims which are intended also to cover equivalents of the specific embodiments.

What is claimed is:

1. A .multi-layer, :toilet-water-flush-awayable napkin such as a disposable diaper, bed napkin and a catamenial device, having as a body-touching layer a thin, soft, relatively loosely textured yet continuity-retaining, moistureabsorbent sheet of cellulose-type fibres; a thin, outer cellulose-type sheet coated on at least one side with a substance imparting water-imperviousness to it and yet enabling it to be flushed away in the toilet water stream; and merely physically impregnated in the uncoated enclosed side of either of said two sheets a relatively continuous intermediate layer of discrete particles in from finely divided to flake form of a dry water absorbent organic substance which, when moist or wet, is inert to any other constituent of the napkin contacted by it and also to the body surface contacted by the napkin, and is a member of the class consisting of blood albumin, egg albumin, natural and synthetic sponges, algin, karaya, tragacanth, and guar gums, and other natural and synthetic gums of polysaccharide character.

2. A multi-layer, toilet-water-flush-awayable napkin such as a disposable diaper, bed napkin and a catamenial device, having as a body-touching layer a thin, soft, relatively loosely textured yet continuity-retaining, moistureabsorbent sheet of cellulose-type fibres; a thin, outer cellulose-type sheet coated on at least one side with a substance imparting water-imperviousness to it and yet enabling it to be flushed away in the toilet water stream; and merely physically impregnated in a supporting separate intermediate sheet of substantially the same character as the body-touching sheet a relatively continuous intermediate layer of discrete particles in from finely divided to flake form of a dry water-absorbent organic substance which, when moist or wet, is inert to any other constituent of the napkin contacted by it and also to the body surface contacted by the napkin, and is a member of the class consisting of blood albumin, egg albumin, natural and synthetic sponges, algin, karaya, tragacanth, and guar gums, and other natural and synthetic gums of polysaccharide character.

3. A multi-layer, toilet-water-flush-awayable napkin such as a disposable diaper, bed napkin and a catamenial device, having as a body-touching layer a thin, soft, relatively loosely textured yet continuity-retaining, moistureabsorbent sheet of cellulose-type fibres; a thin, outer cellulose-type sheet coated on at least one side with a substance imparting water-imperviousness to it and yet enabling it to be flushed away in the toilet water stream; and present to the extent of from about two to about twenty grams per square foot of napkin a relatively continuous intermediate layer of merely physically impregnated discrete particles in from finely divided to flake form of a dry water-absorbent organic substance which, when moist or wet, is inert to any other constituent of the napkin contacted by it and also to the body surface contacted by the napkin, and is a member of the class consisting of blood albumin, egg albumin, natural and synthetic sponges, algin, karaya, tragacanth, and guar gums, and other natural and synthetic gums of polysaccharide character.

4. A multi-la-yer, toilet-water-flush-awayable napkin such as a disposable diaper, bed napkin and a catamenial device, having as a body-touching layer a thin, soft, relatively loosely textured yet continuity-retaining, moistureabsorbent sheet of cellulose-type fibres; a thin, outer celluose-type sheet; and merely physically impregnated in the uncoated enclosed side of either of said two sheets a relatively continuous intermediate layer of discrete particles in from finely divided to flake form of a dry water-absorbent organic substance which, when moist or wet, is inert to any other constituent of the napkin contacted by it and also to the body surface contacted by the napkin, and is a member of the class consisting of blood albumin, egg albumin, natural and synthetic sponges, algin, karaya, tragacanth, and guar gums, and other natural and synthetic gums of polysacch aride character.

5. A multi-layer, toilet-water-flushawayable napkin such as a disposable diaper, bed napkin and a catamenial device, having as a body-touching layer a thin, soft, relatively loosely textured yet continuity-retaining, moistureabsorbent sheet of cellulose-type fibres; a thin, outer cellulose-type sheet; and merely physically impregnated in the uncoated enclosed side of either of said two sheets a relatively continuous intermediate layer of discrete particles in from finely divided to flake form of a dry waterabsorbent gum of polysaccharide character and which, when moist or wet, is inert to any other constituent of the napkin contacted by it and also to the body surfiace contacted by the napkin.

6. A multi-layer napkin as claimed in claim 5, wherein the water-absorbent substance is guar gum and it is impregnated in the enclosed side of the body-touching sheet.

7. A multi-layer napkin as claimed in claim 5, wherein the water-absorbent substance is guar gum and it is impregnated in the enclosed side of the outer cellulosetype sheet.

8. A multi-layer, toilet-water-flush-awayable napkin such as a disposable diaper, bed napkin and a catamenial device, having as a body-touching layer a thin, soft, relatively loosely textured yet continuity-retaining, moistureabsorbent sheet of cellulose-type fibres; a thin, outer cellulose-type sheet; and merely physically impregnated in a supporting separate intermediate sheet of substantially the same character as the body-touching sheet a relatively continuous intermediate layer of discrete particles in from finely divided to flake form of a dry waterabsorbent organic substance which, when moist or wet, is inert to any other constituent of the napkin contacted by it and also to the body surface contacted by the napkin, and is a member of the class consisting of blood albumin, egg albumin, natural and synthetic sponges, algin, karaya, tragacanth, and guar gums, and other natural and synthetic gums of polysacchzaride character.

9. A multi-layer, toilet-waterflush-awayable napkin such as a disposable diaper, bed napkin and a catamenial device, having as a body-touching layer a thin, soft, relatively loosely textured yet continuity-retaining, moistureabsorbent sheet of cellulose-type fibres; a thin, outer cellulose-type sheet; and merely physically impregnated in a supporting separate intermediate sheet of substantially the same character as the body-touching sheet a relatively continuous intermediate layer of discrete particles in from finely divided to flake form of a dry waterabsorbent gum of polysaccharide character and which, when moist or wet, is inert to any other constituent of the napkin contacted by it and also to the body surface contacted by the napkin.

10. A multi-layer napkin as claimed in claim 9, wherein the Water-absorbent substance is guar gum.

11. A multi-layer, toilet-water-flush-awayable napkin such as a disposable diaper, bed napkin and a catamenial device, having as a body-touching layer a thin, soft, relatively loosely textured yet continuity-retaining, moistureabsorbent sheet of cellulose-type fibres; a thin, outer cellulose-type sheet; and present to the extent of from about two to about twenty grams per square foot of napkin a relatively continuous intermediate layer of merely physically impregnated discrete particles in from finely divided to flake form of a dry water-absorbent organic substance which, when moist or wet, is inert to any other constituent of the napkin contacted by it and also to the body surface contacted by the napkin, and is a member of the class consisting of blood albumin, egg albumin, natural and synthetic sponges, algin, karaya, tragacanth, and guar gums, and other natural and synthetic gums of polysaccharide character.

12. A multi-layer, toilet-water-flush-awayable napkin such as a disposable diaper, bed napkin and a catamenial device, having as a body-touching layer a thin, soft, rela tively loosely textured yet continuity-retaining, moistureabsorbent sheet of cellulose-type fibres; a thin, outer References Cited in the fileof this patent UNITED STATES PATENTS Kojima Ian. 5, 1915 Mahler May 22, 1928 Williams Feb. 19, 1929 Wilhelm Mar. 13, 193 4 Gilchrist Oct. 5, 1943 Crane July 10, 1951 Miller Feb. 10, 1953 Hermanson et al Aug. 25, 1953 

1. A MULTI-LAYER, TOILET-WATER-FLUSH-AWAYABLE NAPKIN SUCH AS A DISPOSABLE DIAPER, BED NA PKIN AND A CATAMENIAL DEVICE, HAVING AS A BODY-TOUCHING LAYER A THIN, SOFT, RELATIVELY LOOSELY TEXTURED YET CONTINUITY-RETAINING, MOISTUREABSORBENT SHEET OF CELLULOSE-TYPE FIBERS; A THIN, OUTER CELLULOSE-TYPE SHEET COATED ON AT LEAST ONE SIDE WITH A SUBSTANCE IMPARTING WATER-IMPERVIOUSNESS TO IT AND YET ENABLING IT TO BE FLUSHED AWAY IN THE TOILET WATER STREAM; AND MERELY PHYSICALLY IMPREGNATED IN THE UNCOATED ENCLOSED SIDE OF EITHER OF SAID TWO SHEETS A RELATIVELY CONTINOUS INTERMEDIATE LAYER OF DISCRETE PARTICLES IN FROM FINELY DIVIDED TO FLAKE FORM OF A DRY WATER-ABSORBENT ORGANIC SUBSTANCE WHICH, WHEN MOIST OR WET, IS INERT TO ANY OTHER CONSTITUTENT OF THE NAPKIN CONTACTED BY IT AND ALSO THE BODY SURFACE CONTACTED BY THE NAPKIN, AND IS A MEMEBER OF THE CLASS CONSISTING OF BLOOK ALBUMIN, EGG ALUBIMIN, NATURAL AND SYNTHETIC SPONGES, ALGIN, KARAYA, TRAGACANTH, AND GUAR GUMS, AND OTHER NATURAL AND SYNTHETIC GUMS OF POLYSACCHLARIDE CHARACTER. 